Purnace roll or shaft



Aug. 9, 1932. F. s. SNYDER ET AL 1,870,657

FURNACE ROLL 0R SHAFT Filed Aug. 25, 1930 Patented Au 9, 1932 UNETEDSTATES PATENT GFFHCE FREDERICK S. SNYDER AND CARL H. SIPE, OF BEAVERFALLS, PENNSYLVANIA, AS-

SIGNGBS TO DEMMIE 'I'. SIEE, OF LATROBE, PENNSYLVANTA FUENACE ROLL ORSHAFT Application. filed August 25, 1930. Serial No. 477,514.

()ur invention relates to aroll or shaft serving as means for conveyingarticles through an annealing or normalizing furnace.

., According to previous practice, shafts for 35 pr vent bowing andwarping, either during casting or when operating in the furnace. Thecylindrical construction, furthermore, lacks the strength required forcertain uses.

A further objection to the present type of roll is that defects in thecasting, such as gas pockets, exhibit a tendency to enlarge or erode,which necessitates that they be removed by cutting out a portion of theshaft or roll which is thereby weakened to a dangerous extent.

ll e have invented a hollow roll or shaft for furnaces, which overcomesthe foregoing objections. In accordance with the invention, we provide ahollow roll or shaft, preferably cylindrical, having its ends tapered toform bearing trunnions, the tapered portion of the roll being placedwithin the furnace walls. The roll itself is reinforced bylongitudinally extending radial ribs disposed at right angles within theshaft and formed integral therewith. The cylindrical wall of the rolland the ribs themselves are perforated to permit uniform distribution ofheat, whereby distortion of the roll is largely prevented.

M Our hollow roll, longitudinally reinforced,

is light in weight and characterized by great strength. Because of theventilating perforations, a uniform heat is attained by all parts of theroll. The internal reinforcement provides a rigid construction whichprevents the occurrence of bows, fractures and unequal shrinkage strainswhich might cause fracture of the rolls. In addition, the reinforcementalso provides av better distribution of shrinkage strains during thecastin rocess as well as durin o eration.

i: i D

The reinforced roll also possesses great elasticity, which enables it tostand expansion and contraction, resulting from heating and cooling, towhich the roll is subjected in oper ation.

For a full understanding of the invention, reference is made to theaccompanying drawing illustrating a present preferred embodimentthereof.

In the drawing,

Figure 1 is an elevatioual view partly in section; and

Figure 2 is a transverse sectional view along the line Illl of Figure 1.

Referring in detail to the drawing, our invention comprises a hollowroll h.ving a cylindrical body portion 11 and tapering end portions 12and 13. The tapered end portions 12 and 13 are embedded in the refractory walls 141- of a heat treating furnace. Trunnions 15 and 16project from the tapered ends 12 and 13 and are adapted to be rotatablyseated in suitable bearings for cooperation with any desired drivemechanism.

The interior of the body 11 of the roll 10 is hollow and is providedwith longitudinally extending ribs 17 and 18. The ribs are cast integralwith the roll 10 and lie in radial planes at right angles to each other.The ribs are provided with holes 19 and the cylindrical wall of the roll10 is likewise perforated at 20.

Material en ing discs 21 are carried on the roll or sha-t 10, beingsecured thereto by any suitable means, such as a key 22. The peripheryof the disc may be formed in any suitable manner depending on theproduct to be conveyed, for example, flat for sheets or grooved forrods. The discs are perforated at 23.

The advanta es of the construction described in the foregoing will beapparent to those skilled in the art. The reinforcing ribs assist thecylindrical body of the roll or shaft to withstand the great strainsimposed by the expansion and contraction resulting from temperaturechanges. his is important in furnaces where high temperatures areemployed. As previously stated,

the reinforcement gives a rigid construction which limits thedevelopment of bows and prevents fractures resulting from unequalshrinkage strains.

The reinforcement is also effective in withstanding the strains incidentto shrinkage during casting of the roll. The roll is light in weight andhas great elasticity which further aids it in standing up underconsiderable temperature changes. The perforations in the roll and theribs make possible an easy circulation of the heating gases, so that allportions of the roll have the same temperature. Because of the reductionin weight made possible by the reinforcement, many difficulties ofproper bearing support and lubrication are obviated.

Although we do not desire to be limited to any particular material, weprefer to employ a chromium nickel alloy for casting the roll, becausethis alloy is characterized by resistance to high 'tem eratures. WhileWe have employed herein 0th the terms roll and shaft, it is to beunderstood that they are considered interchangeable and define merely arotating member for the purpose I of conveying material through afurnace chamber.

Although our description and illustration are limited to one form of theinvention, it is obvious that other embodiments may be constructed. Itis not vital, for example, that the body of the roll be cylindrical inform, since other shapes 'may be found suitable. Many other changes may,of course, be made in the illustrated construction, without departingfrom the spirit of the invention.

We claim: 7

1. A furnace conveyor roll comprising a hollow, central cylindricalportion, tapering hollow end portions, integral reduced trunnions, andreinforcing ribs integral with said central and end portions and saidtrunnions, extending continuously between the latter.

2. A furnace conveyor roll comprising a hollow cylindrical portion,reduced integral trunnions, and integral reinforcing ribs within saidcylindrical portion, extending between said trunnions.

3. A furnace conveyor roll comprising a central cylindrical portion,reduced trunnions integral therewith, and continuous ribs within saidcylindrical portion integral therewith and extending substantially fromend to end thereof.

In testimony whereof we have hereunto set our hands.

FREDERICK S. SNYDER. CARL H. SlPE.

